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Background The role of laparoscopy in the management of patients with suspected acute appendicitis remains controversial. It has been suggested that laparoscopy is useful mainly in young women of reproductive age because of the high incidence of wrong diagnosis in these patients. Methods Different management protocols for patients with suspected acute appendicitis were prospectively used in male and female patients; women of reproductive age were treated laparoscopically, while men were randomised to open or laparoscopic appendectomy. Results From September 2002 to September 2005, 132 patients—54 women and 78 men—with suspected acute appendicitis were treated according to the protocol. The incidence of wrong diagnosis in female patients was high (26% and the conversion rate low (5.5%). In contrast, in the laparoscopic male subgroup, these rates showed a reverse relationship (5.2% and 18.5%, respectively). Morbidity did not differ between female and male patients or between the 2 arms of the male group. Laparoscopic appendectomy took longer to perform without affecting significantly the needs for postoperative analgesia, the duration of hospital stay and the time to return to normal activities when compared with open appendectomy in men. Conclusion Laparoscopic appendectomy is at least as safe as the open procedure in the male population, although it does not appear to offer any obvious advantage over the open procedure. The diagnostic advantage that laparoscopy offers to fertile women makes the procedure attractive for this population.  相似文献   
83.
Not fully defined pathophysiologic mechanisms of inflammatory bowel disease (IBD) involve an array of genetic, epigenetic, infectious, physiological and immunological factors. Nowadays, an inadequate activation of the innate immune system to a luminal factor occurring in genetically predisposed subjects is the most widely accepted today. Micro-autoimmune diseases, a group of small, single-stranded, non-coding RNA molecules act as potent negative gene regulators. Beyond cancer and various autoimmune diseases, their impact on IBD has recently been the focus of research. Differential expression of various micro-RNAs has been documented in active and inactive ulcerative colitis, while micro-RNA profile appears to differ between ileal and colonic Crohn's disease. Except for tissue samples, attempts have been made to estimate similar differences at patients' blood samples. Apart from offering new directions in related research, these molecules arise as useful diagnostic tools and potential therapeutic targets. This review focuses on micro-RNA alterations in IBD and their potential implication on immunologic deregulation.  相似文献   
84.
Left ventricular hypertrophy (LVH) with intraventricular septum thickness (IVST) between 1.2 and 1.5 cm in athletes represents a “gray zone” between physiologic adaptation and mild hypertrophic cardiomyopathy (HCM). Various echo and laboratory parameters have been reported till now in the literature to discriminate the “gray zone” entities. Aim of this study was to assess the efficacy of these “classic” parameters in differentiating physiologic LVH in athletes from mild HCM in a highly selected population. Nine highly trained athletes with IVST (1.28 ± 0.07 cm), 9 patients with mild HCM (1.38 ± 0.11 cm), and 26 athletes without LVH (1.06 ± 0.09 cm; P < 0.0005) underwent echocardiographic study, cardiopulmonary treadmill exercise stress test, and brain natriuretic peptide (BNP) measurement before and after exercise. Among all parameters tested, 7 were found to significantly differ between “gray zone” groups. After bootstrapping analysis, it was found that athletes with left ventricular end‐diastolic diameter <4.74 cm, mitral deceleration time >200 ms, isovolumic relaxation time >94 ms, tricuspid E/A < 1.63, septum Em < 9.5 cm/sec, relative wall thickness >0.445, and a BNP value at rest >9.84 pg/mL had a greater possibility for having underlying cardiomyopathy. A 10‐point score based on these parameters showed accuracy (area under the curve = 0.958 [95%CI: 0.738–1.0; P = 0.00005, standard error = 0.0342]) for revealing HCM in a gray zone athletic population. Differentiation of adaptive LVH versus HCM in a gray zone population could be facilitated by recognition of certain features referring to LV dimensions, diastolic function, and BNP.  相似文献   
85.
Farnesyl transferase inhibitors (FTI) exhibit anticancer activity as a single agent in preclinical studies and show promise in combination with other therapeutics in clinical trials. Previous studies show that FTIs arrest cancer cells in mitosis; however, the mechanism by which this occurs is unclear. Here, we observed that treatment of various cancer cell lines with the FTI lonafarnib caused mitotic chromosomal alignment defects, leaving cells in a pseudometaphase state, whereby both aligned chromosomes and chromosomes juxtaposed to the spindle poles (termed "lagging chromosomes") were observed in the same cell. To determine how this occurs, we investigated the functionality of two farnesylated mitotic proteins, CENP-E and CENP-F, which mediate chromosomal capture and alignment. The data show that lonafarnib in proliferating cancer cells depletes CENP-E and CENP-F from metaphase but not prometaphase kinetochores. Loss of CENP-E and CENP-F metaphase localization triggered aberrant chromosomal maintenance, causing aligned chromosomes to be prematurely released from the spindle equator and become lagging chromosomes, resulting in a mitotic delay. Furthermore, lonafarnib treatment reduces sister kinetochore tension and activates the BubR1 spindle checkpoint, suggesting that farnesylation of CENP-E and CENP-F is critical for their functionality in maintaining kinetochore-microtubule interactions. Importantly, apparently similar chromosomal alignment defects were observed in head and neck tumors samples from a phase I trial with lonafarnib, providing support that lonafarnib disrupts chromosomal maintenance in human cancers. Lastly, to examine how farnesylation could regulate CENP-E in mediating kinetochore-microtubule attachments, we examined possible docking motifs of a farnesyl group on the outer surface of the microtubule. This analysis revealed three hydrophobic patches on the tubulin dimer for insertion of a farnesyl group, alluding to the possibility of an association between a farnesyl group and the microtubule.  相似文献   
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The classical phytoestrogens, so far known, constitute a group of plant-derived compounds which include mainly isoflavones, lignans, coumestanes, stilbenes and the flavonoids quercetin and kaempherol. The discovery of many more novel estrogen-like compounds in the plant kingdom demonstrates that the spectrum of phytoestrogens in nature is expanding. The classical as well as the novel phytoestrogens show a complex mode of action via interaction with the nuclear estrogen receptor isoforms ERalpha and ERbeta, exhibiting either estrogen-agonist or estrogen-antagonist effects. Their final biological activity, assessed by cell culture assay systems, animal studies and clinical trials, depends on multiple factors such as the chemical structure of the phytoestrogen, the kind of tissue and cell type, the intrinsic estrogenic status, the route of administration, the metabolism as well as the time and the level of exposure. They are characterized by high tissue specificity and dose-dependent activity. However, although phytoestrogen intake as food or dietary supplements, in particular soya products and the isoflavones genistein and daidzein, has been associated with "health promoting effects", some data indicate increased disease risk. Evidently, phytoestrogen supplementation should be viewed with caution until further studies satisfactorily delineate the effects of individual phytoestrogens on human health and disease.  相似文献   
88.
We present a rare case of primary spleen Echinococcus cyst with rupture evidence due to trauma. The cyst presented with an echogenic pattern at ultrasound examination but subsequent CT study revealed calcification of the cyst wall and signs of rupture. Serological tests were positive for echinococcus and eosinophilia defined. Volume changes of hydatid cyst were not discernible in the imaging studies despite evidence of rupture. Both imaging methods may suggest the diagnosis unless typical diagnostic features are present. Hydatid disease was confirmed histologically on the specimen after surgical excision of the cyst.  相似文献   
89.
The effects of anesthetics on immune cell apoptosis and cytokine stimulation were studied in a prospective study. American Society of Anesthesiologists I/II patients underwent elective inguinal hernia repair or varicose veins stripping surgery and were randomized to either epidural anesthesia (n = 14) or general anesthesia with sevoflurane (n = 19) or propofol (n = 15). Blood was sampled before anesthesia induction (T0), at the end of surgery (T1), and 6 h later (T2). Apoptosis was determined by ANNEXIN-V staining of white blood cells; monocytes were isolated and stimulated for cytokine production. Results were compared with 10 healthy volunteers well-matched for age and gender. Apoptosis of lymphocytes and monocytes was increased in the epidural and sevoflurane groups at T2. Propofol group had increased production of interleukin-6 at T1 and sevoflurane and epidural groups had decreased production of tumor necrosis factor-alpha at T2. Results emphasize the modulation of immune function by epidural and sevoflurane but not propofol anesthesia in a clinical setting.  相似文献   
90.
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